#41  
Old 12-22-2015, 05:03 PM
geeteeohguy's Avatar
geeteeohguy geeteeohguy is offline
Ultimate Warrior
 
Join Date: Dec 2009
Location: Fresno, California
Posts: 5,313
Default

Thanks for posting, Bart. I never knew about the valve guide vents. Wonder how that worked in the GMC trucks with these engines that were used on job sites off road and in the desert? Very interesting.

__________________
Jeff
  #42  
Old 12-22-2015, 11:57 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

It's a lot of fun checking out one of these early Pontiac V8s and seeing the differences between it and the later ones we're all used to.

They are the ones that most of us won't ever get a chance to work on. We pass them by, mainly because we know the small-valve press-in stud cylinder heads are 'inferior' to the later ones and the blocks won't bolt up to modern transmissions. They're no longer favored by the street performance crowd because of the improved designs of their later '60s and early '70s brethren.

But 4 of these 1959 389s (4-bolt main versions in heavily modified form) did power the fastest Pontiac-powered car ever built.

Pretty cool if you ask me.

__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #43  
Old 12-23-2015, 01:08 PM
Bill Hanlon's Avatar
Bill Hanlon Bill Hanlon is offline
Ultimate Warrior
 
Join Date: Feb 2005
Location: Fredericksburg, TX
Posts: 2,349
Default

Quote:
Originally Posted by b-man View Post
But 4 of these 1959 389s (4-bolt main versions in heavily modified form) did power the fastest Pontiac-powered car ever built.

Pretty cool if you ask me.
https://en.wikipedia.org/wiki/Mickey...dRecordCar.jpg

__________________
My Pontiac is a '57 GMC with its original 347" Pontiac V8 and dual-range Hydra-Matic.
  #44  
Old 12-24-2015, 10:33 PM
77 TRASHCAN's Avatar
77 TRASHCAN 77 TRASHCAN is offline
Ultimate Warrior
 
Join Date: Oct 2008
Location: 31May2013 Temporary home to the world's widest (that we know of) tornado. Lord, NO more Please...
Posts: 6,591
Default

It amazes me what Smokey was able to do with these early parts. The SD stuff to was better, I just don't know how much better than the stock heads...

__________________
1977 Black Trans Am 180 HP Auto, essentially base model T/A.
I'm the original owner, purchased May 7, 1977.

Shut it off
Shut it off
Buddy, I just shut your Prius down...
  #45  
Old 12-27-2015, 12:28 AM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default Vintage Tri-Power Intake

I picked up a very nice 1959 Tri-Power intake today.

1959 was the 3rd year that Pontiac offered the Tri-Power option, however the large-base Rochester carbs were used as the secondary carbs for the first time in 1959.

Now to find a center carb and a front carb, I already have a rear carb.









Casting # 532422



Date code 'L 15 8' (December 15th 1958)


__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #46  
Old 12-27-2015, 08:42 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

Decided it was time to drag out the ol' 389 and drop the pan today. Topped it off with a nice '67 326 2-barrel air cleaner I had laying around just for grins.



The pan practically fell off after removing all of the bolts, the gaskets were old and tired. There was a pretty big leak going on at the rear of the pan from what I could see.



The sludge buildup in the sump was pretty thick, anywhere from 3/8" to 3/4" depending on the shape of the sump area. The drain plug was almost buried in sludge.



Here's what I harvested from the sump, a pretty good amount.





One of the features of the older Pontiac engines was this 'floating' oil pump pickup. Perhaps it was designed to keep the pickup above the layer of sludge that older engines were known to accumulate over time, surely the engineers knew that non-detergent oils and leaded gas would be laying down a decent amount of sludge during the engines' service life.





Here's a look at the windage tray/sump baffle, a design that was used up through 1964.





Very thick #1 main cap, looks to be at least 1/4" thicker than on '61 and later engines.



The connecting rod nuts are backed up by a sheetmetal locking nut, an interesting feature that I didn't expect to see.



Here you can see the heavy webbing cast into the block on the passenger side oil pan rail area, a feature that would disappear from common production blocks after 1960.




__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #47  
Old 12-27-2015, 09:17 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

The exhaust manifolds cleaned up nicely.

Pontiac exhaust manifolds have a nice free-flowing design, much less restricted than the standard exhaust manifolds of most other makes.





I'm particularly fond of the driver's side manifold with the center outlet, purely from an aesthetic standpoint. A pair of these would look great on a fenderless late '20s or early '30s roadster with an open engine compartment.






__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #48  
Old 12-28-2015, 03:10 AM
GRX's Avatar
GRX GRX is offline
Ultimate Warrior
 
Join Date: Jul 2006
Location: Maryland
Posts: 1,400
Default

Interesting the center dump manifold has a divider where the other does not.

  #49  
Old 12-28-2015, 11:47 AM
pfilean's Avatar
pfilean pfilean is offline
Ultimate Warrior
 
Join Date: May 2007
Location: West Des Moines, IA
Posts: 1,932
Default

Quote:
The connecting rod nuts are backed up by a sheet metal locking nut, an interesting feature that I didn't expect to see.
Used to see those all the time on 216/235 Chevy 6s. Maybe common on GM whereas I remember Fords with tie wires to do the same job.

  #50  
Old 12-28-2015, 03:07 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

Quote:
Originally Posted by GRX View Post
Interesting the center dump manifold has a divider where the other does not.
It seems up to a certain year that all of the driver's side manifolds had the divider, both center dump and rear dump.

Here's a set of 1964 GTO/Le Mans manifolds.





Now a set of 1974 manifolds, no divider on the driver's side.





Set of 1969 GP and Firebird manifolds, the driver's side center dump is divided.









__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #51  
Old 12-28-2015, 05:50 PM
Tom Vaught's Avatar
Tom Vaught Tom Vaught is offline
Boost Engineer
 
Join Date: Dec 2001
Location: The United States of America
Posts: 31,294
Default

The Driver's side manifold has the #5 cylinder firing right before the #7 cylinder fires.

If the manifold is open, no divider, you would think that exhaust gas from the #5 would try to flow toward the #7 port and would tend to block some of the exhaust gas trying to exit the #7 cylinder. More back pressure in that #7 cylinder vs the other cylinders.

Forcing the #5 exhaust to move toward the manifold discharge flange would remove some of that backpressure when #7 exhaust valve opens.

Tom V.

__________________
"Engineers do stuff for reasons" Tom Vaught

Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward.
  #52  
Old 12-28-2015, 08:27 PM
GRX's Avatar
GRX GRX is offline
Ultimate Warrior
 
Join Date: Jul 2006
Location: Maryland
Posts: 1,400
Default

"It seems up to a certain year that all of the driver's side manifolds had the divider, both center dump and rear dump."

"The Driver's side manifold has the #5 cylinder firing right before the #7 cylinder fires."

Ahhh ... makes more sense now that I look inside one of my logs and see the central divider extends almost to the outlet, essentially isolating #5 from the other three on that bank. Guess by the mid-70s performance was no longer a concern so it was eliminated. Makes me wonder how much performance was really gained with the ra3 manifolds and their 4 internal dividers isolating all the pulses.
Attached Thumbnails
Click image for larger version

Name:	exhman1a.jpg
Views:	51
Size:	57.5 KB
ID:	416770  

__________________
1969 GTO hard top ~ Std bore 400, '70-RA3 block, 670 heads, Bal. & Blue... M22, 12-bolt w/3:55s
  #53  
Old 12-28-2015, 08:36 PM
Tom Vaught's Avatar
Tom Vaught Tom Vaught is offline
Boost Engineer
 
Join Date: Dec 2001
Location: The United States of America
Posts: 31,294
Default

The engines probably made a slight bit more power with the more radical camshafts due to less EGR back flow to the next cylinder in line.

Tom V.

__________________
"Engineers do stuff for reasons" Tom Vaught

Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward.
  #54  
Old 12-28-2015, 08:51 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default More Tri-Power.....

I cleaned up my rear carb today and took a few pics.

First off, here's what's left of the original foil ID tag. Part number 7013065 tells us it's a rear carb used from 1959 - 1962 on both manual and auto trans 389 engines.



Top view of the carb where you can see the large vacuum diaphragm that was used to actuate both the front and rear secondary carbs depending upon engine demand (wide-open throttle).



That vacuum actuator is huge (camera perspective makes it look even bigger), it has to be in order to pull those two carbs wide-open.



A look at the linkage from the actuator to the throttle shaft.





I removed the actuator since I'll probably be using 1965 - 1966 manual-trans mechanical linkage instead. All Pontiac Tri-Powers had vacuum actuated secondary carbs up until the introduction of the 1965 GTO stick-shift engines. All GTO auto trans Tri-Powers were vacuum actuated.

A lot of Tri-Power owners didn't like the scary one or two seconds that the vacuum-controlled secondary carbs took to close after lifting off the throttle, and who could blame them. Many were converted to aftermarket mechanical linkage and some owners had the Tri-Power setups removed altogether and replaced with a standard single 2-barrel or 4-barrel.





I checked the angle of the throttle plates at wide-open position and found that they don't open all the way. Very likely this was engineered into the setup to keep from adding too much airflow for the engine to handle.





Here's the stop on the side of the throttle body.


__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #55  
Old 12-28-2015, 10:05 PM
77 TRASHCAN's Avatar
77 TRASHCAN 77 TRASHCAN is offline
Ultimate Warrior
 
Join Date: Oct 2008
Location: 31May2013 Temporary home to the world's widest (that we know of) tornado. Lord, NO more Please...
Posts: 6,591
Default

Anyone reproduce the carb tags?

__________________
1977 Black Trans Am 180 HP Auto, essentially base model T/A.
I'm the original owner, purchased May 7, 1977.

Shut it off
Shut it off
Buddy, I just shut your Prius down...
  #56  
Old 12-28-2015, 10:27 PM
CATBIRD CATBIRD is offline
Senior Member
 
Join Date: Oct 2005
Posts: 226
Default

Bart.....no matter what the carb tag states, what you have there is the front carb. The vacuum fitting for the power brakes goes between the front and center carbs. The vacuum chamber for the front and rear carb mounts on the front left of the front carb. The rear carb has no vacuum outlet in the base......John

  #57  
Old 12-28-2015, 10:38 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

Quote:
Originally Posted by CATBIRD View Post
Bart.....no matter what the carb tag states, what you have there is the front carb. The vacuum fitting for the power brakes goes between the front and center carbs. The vacuum chamber for the front and rear carb mounts on the front left of the front carb. The rear carb has no vacuum outlet in the base......John
Thanks John, I sort of suspected that from looking at the positioning of the vacuum diaphragm.

Either way, I'm happy to have at least one of the trio in hand.

Bart

__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #58  
Old 12-30-2015, 09:47 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default Today I decided.....

.....to check the condition of the reverse-flow cooling system pieces.

So off came the valve covers, intake manifold and valley pan.



The water pump still turns freely and the pump cavity looks to be in pretty decent shape.



After removing the balancer I can see the primitive cork front seal assembly has long ago stopped doing any sealing. Getting the front cover cut for a modern neoprene lip seal is definitely on my list of things to do.





Timing cover assembly removed, there's really no other way to get access to the cooling tubes in the heads since the rubber connecting hoses are rock-hard.





First peek at one of the thin stainless steel cooling tubes, driver's side shown here. I was sort of wondering if they'd even be in there at first.





Passenger side tube, clearly somebody in the past just crammed in the last bit and made a mess of the end of the tube, worse than on the driver's side tube.



I managed to straighten the end of the tube enough using long needle nose pliers and a thin screwdriver to be able to coax it out.



Here you can see one of the gusher holes in the tube that directs the coolant toward the valve seats.



Here's the cooling tube in all it's glory, there's really not a lot of information or pictures of these things available.





The cavity in the head is cast so that you can't insert the tube in the wrong orientation.



The driver's side tube was a lot more stubborn, I ended up using a C-clamp to hold the pliers tightly and then I tapped on the clamp with a lead hammer to finally free it.



Here again you can see the gusher holes in the tube pointing inward toward the valve seats.



Driver's side tube laid out for inspection. I'll have to do some careful straightening of both ends of these tubes before putting them back in the heads.





Another attempt at showing the shape of the cooling tube cavity in the head.



Cooling elbows after extracting them from the old hoses.





Timing cover ready for a long soaking in some cleaning solution.



I stuffed some rags into the cooling passages at both ends of the heads to keep any errant coolant or rust flakes out of the engine while I flip it upside down.



Some nice green coolant trickled out, a good sign.



The bottom end looks fairly clean.



A closer look at the heavy webbing cast into the lower end of the passenger side of the block.



A better look at the thick front main cap.



Measuring the the cap thickness with my cheap Harbor Freight garage calipers.



We have a 1.375" measurement.



All of the connecting rods have their corresponding cylinder numbers stamped in, telling me that someone's been inside here before.



Not only that, I see clear evidence of some knurling on the piston skirts as well.





I pulled the windage tray and dipstick tube, exposing some pretty clean-looking rear crank counterweights.



The oil pump pickup is pretty clogged-up with crud, I'll probably treat this old soldier to a lightly used modern Melling M54D 60 psi pump and pickup before buttoning it up.


__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
  #59  
Old 12-30-2015, 09:58 PM
Ben M.'s Avatar
Ben M. Ben M. is offline
Ultimate Warrior
 
Join Date: Jan 2004
Posts: 2,796
Default

Is there any source available for those cooling tubes in the head? Doesn't seem like it would be overly difficult to make them, but I'm sure the demand is very limited.

  #60  
Old 12-30-2015, 10:03 PM
b-man's Avatar
b-man b-man is offline
Moderator
 
Join Date: Sep 2002
Location: Sunny So Cal
Posts: 16,411
Default

Quote:
Originally Posted by Ben M. View Post
Is there any source available for those cooling tubes in the head? Doesn't seem like it would be overly difficult to make them, but I'm sure the demand is very limited.
Other than finding NOS pieces (good luck) or good used I seriously doubt it.

__________________
1964 Tempest Coupe LS3/4L70E/3.42
1964 Le Mans Convertible 421 HO/TH350/2.56
2002 WS6 Convertible LS1/4L60E/3.23
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:00 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017